Our results indicate that oxidation of TAF10 by LOXL2 induces its release from its promoters, leading to a block in TFIID-dependent gene transcription. Since TFIID complex is crucial for the expression of Nanog, Klf4, Sox2 and Oct4 and for maintaining the pluripotent state of embryonic stem cells, TAF10 oxidation by LOXL2 leads to inactivation of the pluripotency genes and a loss of pluripotent capacity in embryonic stem cells. Moreover, in vivo results demonstrate an essential role of LOXL2 in neural differentiation during zebrafish development: in the absence of LOXL2 the neural progenitor gene Sox2 is aberrantly overexpressed and neural differentiation is impaired.
LOXL2 Oxidizes Methylated TAF10 and Controls TFIID-Dependent Genes during Neural Progenitor Differentiation.
Specimen part
View SamplesLeptospirosis is a neglected zoonotic disease of global importance. Despite its prevalence, pathogenesis is still poorly understood. Our aim was to discover transcripts responsable for pathogenicity of leptospirosis. We compared the transcriptome profiles of saprophyte, attenuated and virulent strain of Leptospira spp.
Transcriptome datasets of macrophages infected with different strains of <i>Leptospira</i> spp.
Cell line
View SamplesAlthough heterochromatin is enriched with repressive traits, it is also actively transcribed, giving rise to large amounts of non-coding RNAs. Although these RNAs are responsible for the formation and maintenance of heterochromatin, little is known about how their transcription is regulated. Here we show that the Snail1 transcription factor represses pericentromeric transcription, acting through the H3K4 deaminase LOXL2. Since Snail1 plays a key role in the epithelial to mesenchymal transition (EMT), we analyzed the regulation of mouse heterochromatin transcription in this process. At the onset of EMT, one of the major structural heterochromatin proteins, HP1a, is transiently released from heterochromatin foci in a Snail1/LOXL2dependent manner during EMT, concomitantly with a down-regulation of major satellite transcription. Global transcriptome analysis indicated that ectopic expression of heterochromatin transcripts affects the transcription profile of EMT-related genes. Additionally, preventing the down-regulation of major satellite transcripts compromised the migratory and invasive behavior of mesenchymal cells. We propose that Snail1 regulates heterochromatin transcription through the histone-modifying enzyme, LOXL2, thus creating the favorable transcriptional state necessary for completing EMT.
Regulation of heterochromatin transcription by Snail1/LOXL2 during epithelial-to-mesenchymal transition.
Cell line, Treatment
View SamplesGene expression of T47D-MTVL human breast cancer cells expressing Dox-inducible shRNAs against histone H1.4 (120sh) or multiple H1 variants (225sh) Overall design: Stable breast cancer-derived cell lines expressing an shRNA against one of each of the histone H1 isoforms in response to doxycycline (Dox) were grown for six days in the presence or absence of Doxicycline, RNA extracted and high-thorughput sequenced. Cell lines used: inducible shRNA against H1.4 or multiple H1 variants and random shRNA-expression vector.
Histone H1 depletion triggers an interferon response in cancer cells via activation of heterochromatic repeats.
Cell line, Subject
View SamplesGene expression from MDA-MB-231 cells shControl and shLOXL2.
Lysyl oxidase-like 2 (LOXL2) oxidizes trimethylated lysine 4 in histone H3.
Cell line
View SamplesHuman disease caused by highly pathogenic avian influenza (HPAI) H5N1 can lead to a rapidly progressive viral pneumonia leading to acute respiratory distress syndrome. There is increasing evidence suggests a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. The key target cells for the virus in the lung are the alveolar epithelium and alveolar macrophages, and previous data has shown that compared to seasonal human influenza viruses, equivalent infecting doses of H5N1 viruses markedly up-regulate pro-inflammatory cytokines in both primary cell types in vitro. The dysregulation of H5N1-induced host responses is therefore important for understanding the viral pathogenesis.
Systems-level comparison of host-responses elicited by avian H5N1 and seasonal H1N1 influenza viruses in primary human macrophages.
Specimen part, Subject, Time
View SamplesThe multiple claims about reactivation of the embryonic stem cell (ESC) pluripotency factor OCT4 in somatic cells are highly controversial due to the fact that there is no direct evidence that OCT4 has a functional role in cells other than ESCs. Herein we demonstrate that smooth muscle cell (SMC)-specific knockout of Oct4 within atherosclerotic mice resulted in increased lesion size and multiple changes consistent with decreased plaque stability. SMC-lineage tracing studies showed that lesions from SMC-specific conditional Oct4 KO mice had a reduced number of SMCs likely due to impaired SMC migration. RNA-seq analysis of lesion specimens showed that loss of Oct4 in SMCs was associated with marked activation of genes associated with inflammation and suppression of genes associated with cell migration, a number of which were shown to be activated in cultured SMCs by the combination of hypoxia and oxidized phospholipids in an OCT4-dependent manner. Activation of Oct4 within SMCs was associated with hydroxymethylation of the Oct4 promoter and was HIF1a- and KLF4-dependent. Results provide the first genetic evidence that OCT4 plays a functional role in somatic cells and highlight the importance of further investigation of possible OCT4 functions in somatic cells. Overall design: In vivo: mRNA profiles of 18 week fed Western diet wild type (WT) and Oct4-/- mice were generated by deep sequencing, four animals per group, using Illumina HiSeq 2000. In vitro: a smooth muscle cell wild type (WT) and Oct4-/- (KO) primary aortic cell line was generated and used. mRNA profiles were generated by deep sequencing, in triplicates, using Illumina HiSeq 2000, for the following groups: WT-normoxia-vehicle; WT-normoxia-POVPC; KO-normoxia-vehicle; KO-normoxia-POVP; WT-hypoxia-vehicle; WT-hypoxia-POVPC; KO-hypoxia-vehicle; and KO-hypoxia-POVPC.
Perivascular cell-specific knockout of the stem cell pluripotency gene Oct4 inhibits angiogenesis.
Specimen part, Cell line, Treatment, Subject
View SamplesBackground: Increasing evidence indicates stem cell transplantation may be an effective stroke treatment but little is known about the direct impact of transplanted cells on injured brain tissue. We investigated the effects of lineage negative murine hematopoietic stem/progenitor cells (HSPCs) on the cerebral microcirculation following ischemia-reperfusion injury (I/RI). Following subsequent evaluation of the mRNA transcriptome of the explanted HSPCs, we assessed whether metallothionein (MT)-1, (increased in explanted HSPCs from I/R mice) administration was able to evoke similar neuro-protection following cerebral I/RI. Methods and Results: Murine HSPCs administered intravenously 24 hours (h) post cerebral I/R were selectively recruited to the brain of I/RI mice. Mice treated with HSPCs displayed decreased disease severity for up to 2-weeks post cerebral I/R, as evidenced by decreased mortality rate, decreased infarct volume, improved functional outcome, reduced microglial activation and elevated plasma levels of anti-inflammatory interleukin-10. Using confocal intravital microscopy, we found that transplanted cells had emigrated into the brain parenchyma and that RNA-seq analysis of explanted HSPCs indicated significantly increased levels of metallothionein transcripts, in particular MT-1. We further determined that treatment of mice with MT-1 significantly reduced neurological score and IV. Conclusions: These studies provide further evidence for HSPCs as a promising therapeutic strategy in promoting repair following cerebral I/RI, potentially via a MT-1 mechanism. Overall design: Murine HSPCs were administered into mice with I/RI intravenously 24 hours post cerebral I/R and selectively recruited to the brain. RNA profiles of explanted HSPCs were determined by RNA sequencing.
Metallothionein I as a direct link between therapeutic hematopoietic stem/progenitor cells and cerebral protection in stroke.
Specimen part, Cell line, Treatment, Subject
View SamplesPandemic influenza H1N1 (pdmH1N1) virus causes mild disease in humans but occasionally leads to severe complications and even death, especially in those who are pregnant or have underlying disease. Cytokine responses induced by pdmH1N1 viruses in vitro are comparable to other seasonal influenza viruses, suggesting the cytokine dysregulation as seen in H5N1 infection is not a feature of the pdmH1N1 virus. However, a comprehensive gene expression profile of pdmH1N1 in relevant primary human cells in vitro has not been reported. Type I alveolar epithelial cells are a key target cell in pdmH1N1 pneumonia. We carried out a comprehensive gene expression profiling using the Affymetrix microarray platform to compare the transcriptomes of primary human alveolar type I-like alveolar epithelial cells infected with pdmH1N1 or seasonal H1N1 virus.
Systems-level comparison of host responses induced by pandemic and seasonal influenza A H1N1 viruses in primary human type I-like alveolar epithelial cells in vitro.
Specimen part, Subject, Time
View SamplesOsteoarthritis (OA) of the hand is a common disease resulting in pain and impaired function. The pathogenesis of hand OA (HOA) is elusive and models to study it have not been described so far. Culture of chondrocytes is a model to study the development of cartilage degeneration, which is a hallmark of OA and well established in OA of the knee and hip. In the current study we investigated the feasibility human chondrocyte culture derived from proximal interphalangeal (PIP) finger joints of dissecting room cadavers. Index and middle fingers without signs of osteoarthritis were obtained from 30 cadavers using two different protocols. Hyaline cartilage from both articulating surfaces of the proximal interphalangeal (PIP) joint was harvested and digested in collagenase. Cultured chondrocytes were monitored for contamination, viability, and expression of chondrocyte specific genes. Chondrocytes derived from knee joints of the cadavers were cultured under identical conditions. Gene expression comparing chondrocytes from PIP and knee joints was carried out using Affymetrix GeneChip Human 2.0 ST arrays. The resulting differentially expressed genes were validated by real-time PCR and immunohistochemistry.Chondrocytes harvested up to 101 hours after death of the donors were viable. mRNA expression of collagen 2A1, aggrecan and Sox9 was significantly higher in chondrocytes as compared to cultured fibroblasts. Comparison of gene expression by chondrocytes from PIP and knee joints yielded 528 differentially expressed genes. Chondrocytes from the same joint region had a higher grade of similarity than chondrocytes of the same individual. These results were validated using real-time PCR and immunohistochemistry.We demonstrate for the first time a reliable method for culture of chondrocytes derived from PIP joints. PIP chondrocytes show a specific gene expression pattern and could be used as tool to study cartilage degeneration in HOA.
Chondrocyte cultures from human proximal interphalangeal finger joints.
Sex, Specimen part
View Samples